Prevention of environmental pollution from agricultural activity: guidance

Code of good practice, giving practical advice to farmers and others on minimising pollution.

Section 8: sheep dip


**1. Comply with the Groundwater Regulations 1998.

**2. Ensure that disposal of waste sheep dip to land is carried out in accordance with an authorisation issued by SEPA.

**3. Have staff properly trained in the correct use of dips and dipping practice and ensure that they understand the very harmful effects of sheep dip on aquatic life.

**4. Only purchase sheep dip if you hold the required Certificate of Competence.

5. Follow the Sheep Dipping Code of Practice.

6. Plan all aspects of the dipping operation in advance, identifying all possible pollution risks and taking action to minimise these risks as far as possible.

7. Ensure that a Contingency Plan is drawn up to deal with any potential spillage.

8. Ensure that proprietary kits or absorbent materials are readily available to deal with spillages.

9. Strictly follow manufacturers' instructions if detoxifying waste sheep dip.

10. Ensure that when mobile dipping is carried out, registered mobile dipping contractors are used.

11. Adopt high standards of flock management that aim to minimise the possibility of ectoparasitic infection on your farm.

12. Wear appropriate Personal Protective Equipment.

13. Allow sheep to drain in their drip pen for at least 10 minutes and prevent run off to any watercourse.

14. Rinse empty containers thoroughly and add washings to the dip bath.


**1. Don't allow dip to enter a watercourse. This will result in serious pollution, and may result in enforcement action being taken by SEPA under environmental legislation.

**2. Don't use dips that are not approved.

**3. Don't delay in contacting SEPA regarding any pollution incident involving sheep dip.

**4. Don't store waste sheep dip for re-use. This is against veterinary medicines legislation and could result in harm to animal health.

**5. Don't bury empty containers without obtaining a landfill permit.

6. Don't be afraid to seek veterinary advice as to the most appropriate method of ectoparasite control for your flock.

7. Don't site dippers within 10m of a watercourse and certainly not within 50m of water supplies.

8. Don't ignore the need to carry out regular maintenance of sheep dipping facilities, taking account of signs of cracking, wear, damage or corrosion.

9. Don't leave a full dip bath uncovered or unattended.

10. Don't delay emptying the dip bath, unless weather conditions do not permit safe disposal.

11. Don't allow the dip bath to overflow.


8.1 Sheep dipping can play an important role in the maintenance of good animal welfare. The chemicals used in dips are highly toxic and, if used properly, can be very effective against parasites that colonise sheep skins and fleeces. However, if good practice is not followed, this can have devastating consequences for the water environment. Aquatic life in many miles of watercourses in Scotland has been killed as a result of the entry of tiny amounts of dip. Groundwater can also be put at risk if dipping-related activities are not managed properly. There are a number of legislative requirements for the handling and disposal of sheep dip as explained below.

8.2 Treatments containing Organophosphates (OPs) and Synthetic Pyrethroids (SPs) are extremely toxic, even at very low concentrations. This is especially the case with SP-based dips, which are 100 times more toxic to aquatic life than OP-based dips. The improper use and disposal of all dips also poses a significant risk of contaminating drinking water supplies taken from groundwater (e.g. springs, wells or boreholes). Groundwater and surface water are interlinked and therefore pollution of one can seriously affect the quality of the other.

8.3 Adherence to the Groundwater Regulations 1998 is a Cross Compliance Statutory Management Requirement. Farmers are required to ensure that certain listed substances, including waste sheep dip, do not enter or cause pollution of groundwater. In addition to giving SEPA the power to issue a Notice on persons involved in any activity which poses a risk to groundwater, the Regulations allow Scottish Ministers to approve the issuing of Codes of Practice to those involved in activities that pose a risk. The disposal of waste sheep dip must be authorised by SEPA and all other activities associated with sheep dipping should be carried out in accordance with the Sheep Dipping Code of Practice for Scottish Farmers, Crofters and Contractors - Groundwater Regulations 1998. This Code has been published to provide practical guidance on the steps to take before, during and after dipping so as to prevent adverse impacts on groundwater.

8.4 The purchaser of any sheep dip product must hold a Certificate of Competence in the Safe Use of Sheep Dips to demonstrate that they will use dips responsibly. All people managing or carrying out dipping must be trained in the safe use and disposal of sheep dips to ensure adequate knowledge of:

  • personal health and safety

  • animal welfare

  • environmental protection

8.5 Further details of training and certification can be found in the National Proficiency Test Council publication, Certificate of Competence in the Safe Use of Sheep Dips (1998).

8.6 New controls on agricultural wastes, which include spent sheep dip, were introduced in 2004. Contact your local SEPA office for further advice on if and how these controls apply.

Good sheep flock management

8.7 Adopt flock management techniques that ensure chemical treatments (and sheep dips in particular) are limited to the minimum necessary to maintain animal welfare. This can make good financial, as well as environmental, sense.

8.8 Only use treatments when they are strictly needed for animal health reasons. Other authorised alternatives to plunge dips, such as pour-on products or injectables, may be effective for maintaining the health of flocks and should be considered. If in doubt about what product to use, seek advice from a veterinary surgeon.

8.9 It is vital that records are kept of the date and location of dipping, and the type of dip used. Records must also be kept in respect of any authorised disposal of waste sheep dip to land in accordance with an authorisation granted by SEPA.

Before dipping

8.10 The risk to the aquatic environment from sheep dipping can be confined to the few days each year when dipping is taking place and tight management of the operation during this time can significantly reduce this risk.

8.11 Plan all aspects of your dipping operation _ where the dip will be stored; how it will be transported to the dipper; how the dipper will be filled and emptied; how and where the waste dip will be disposed of and what to do in the event of anything going wrong.

8.12 Limiting the purchase of dip concentrate to the minimum quantity necessary to meet the manufacturers dipping instructions will help to reduce the amount of waste dip produced. Only licensed products should be purchased and used. On arrival at the farm, dip concentrate must be stored in a secure store, safely locked and clearly identified. 

8.13 Dipping facilities must be sited and constructed in such a way as to prevent entry of water from the surrounding land, and to ensure no loss or leakage from the dip occurs above or below ground. In particular, dipping facilities should:

  • be of a one-piece, prefabricated construction
  • not be cracked, or have any drain holes
  • be fitted with splash boards and kerbs
  • have impermeable drip pens draining or directing all drippings back to the dip bath
  • be sited at least 10m away from a watercourse or 50m away from wells, springs or boreholes

8.14 It is important that the condition of the dipper is examined before use. If the dipper is damaged, it should be replaced.

8.15 During filling, the dipper must not be allowed to overflow. Avoid any possibility of dip being siphoned or sucked back into the water system.

During dipping

8.16 Effective, safe dipping should be carried out in accordance with the manufacturer's instructions on the product label. Dip concentrate should be poured into the dip bath slowly. To reduce excess splashing, work to a routine, calmly and in control. The contents of the dip bath should be kept well mixed and maintained at the recommended strength.

8.17 Personal Protective Equipment should be used at all times during dipping.

After dipping

8.18 After dipping, sheep should be allowed to drain in a drip pen for at least 10 minutes, to allow surplus dip to drain completely back to the dipper. Once sheep have left the drip pen, subsequent holding areas and their return route to grazing should be chosen such that there is no contact with watercourses and a minimum of 50 metres distance from any spring, well or borehole used as a drinking water supply. Waterlogged ground and hard surfaces, such as metalled roads, should also be avoided.

8.19 Do not delay emptying the dip bath unless weather conditions do not permit safe disposal. A full dip bath should never be left unattended. The dipper should be emptied as soon as possible by a slurry tanker or pump and disposed of in accordance with an authorisation granted by SEPA under the Groundwater Regulations 1998 - contact SEPA for advice on this. Waste sheep dip should not be stored for re-use. This is against veterinary medicines legislation and could result in harm to animal health. Spent dip must never be discharged to a watercourse. The drip pens and dipper should then be washed thoroughly with clean water and the washings removed to the authorised disposal site. The dipper should then be made secure so that rain cannot infiltrate and cause overflow.

8.20 Subject to an authorisation issued by SEPA, the preferred method of disposal is the spreading of diluted spent dip on land. Prior to spreading, waste sheep dip should be further diluted with a minimum 1 part dip to 3 parts slurry or water, before application to land which has been assessed as suitable.

8.21 Key criteria for suitable land for disposal include areas that:

  • are well-vegetated, and flat or gently-sloping, so as to prevent either surface run-off or 'pooling' of the waste dip on the disposal area

  • are more than 10m from a watercourse

  • are more than 50m from any spring, well or borehole

  • are more than 500m from any borehole, or 500m upslope of any spring or well, used for drinking water supply

  • do not have saturated, waterlogged, cracked or frozen soil (to a depth of more than 50 millimetres)

  • are freely or moderately drained

  • have deep loamy or peaty soils

8.22 SEPA should be contacted for advice in the event of potential disposal areas not being able to meet one or more of these criteria.

8.23 The maximum surface spreading rate will be specified by SEPA when it grants an authorisation.

8.24 When further treating, or detoxifying, waste sheep dip prior to disposal, it is vital that the particular treatment employed is that specified by the manufacturer for the dip type and formulation used. SEPA should be consulted for advice before undertaking treatment. On no account must waste dip be treated using a method designed for another product. The disposal of treated waste sheep dip will be subject to an authorisation from SEPA. Even when treated, waste sheep dip remains highly toxic, and the same level of care must be adopted during its handling, as for untreated dip.

8.25 Empty dip containers and measuring vessels must be thoroughly rinsed out and the rinse water should be returned to the dip bath before dipping. The cleaned containers should never be reused or left lying about the pens, as they can be a source of pollution and a potential safety hazard due to the presence of dip residues. Cleaned containers can be disposed of via the local authority waste collection service (if available) or by a registered waste disposal contractor. The burning of empty, even rinsed, containers is not advised. Farmers should enquire as to whether any surplus concentrate may be returned to the supplier. Alternatively, such dip may be disposed of by using the services of a registered waste disposal contractor. The burial of empty sheep dip containers without a permit is a contravention of the Landfill (Scotland) Regulations 2003.

Mobile dipping, showers and jetters

8.26 Use of mobile dipping units, often operated by contractors, has become more popular in recent years. It is vital, therefore, that the site selected for mobile dipping is 'low risk' from the point of view of the environment and that the design, construction and overall management is of a high standard.

8.27 At farm steadings, mobile dippers pose an environmental risk if sited on impermeable surfaces close to surface water drainage systems. Out in the field, mobile dippers pose a particular risk of pollution if situated close to a watercourse, well, borehole or field drain. Sealed drainage systems and suitable collection facilities should be provided to contain any spillages, leaks or drainage from equipment or from sheep immediately after treatment. Provision should be made to collect any drainage or drippings from treated sheep in a similar manner to that for static sheep dippers.

8.28 Field-based mobile dippers should be located more than 10m from watercourses and 50m from any spring, well or borehole. Sites chosen should be flat, or gently sloping, with well established grass cover and be underlain by at least 15cm top soil, preferably with a total soil depth of at least 60cm to rock. The area should be free from flooding, surface ponding or waterlogging and not be frozen or compacted

8.29 The issue of who is actually responsible for the disposal of waste sheep dip, the farmer or the mobile dipping contractor, must be resolved prior to the commencement of dipping.

8.30 The use of showers and jetters to apply dip to sheep can also pose increased environmental risks. The same high standards of management referred to above for the use of mobile dippers must also be applied in respect of showers and jetters. It should be noted, however, that product label recommendations might not permit the use of OP and SP sheep dips in this manner.

Safety precautions

8.31 It is important to be prepared for any spillage as swift action can prevent a serious pollution incident. All staff involved in the dipping operation should be aware of what action needs to be taken in the event of a spillage. Spillages should be immediately washed into the dip bath and not allowed to enter any drain that might discharge to a watercourse.

8.32 Proprietary kits or absorbent materials should be available at the dipping site to deal with spillages. If a spillage occurs away from the immediate vicinity of the dipper, use absorbent materials to contain it, and collect and transfer all contaminated material, including soil, to a clearly labelled sealed container for collection by a registered waste disposal contractor.

8.33 You should alert SEPA immediately regarding any pollution incident involving sheep dip by telephoning the 24-hour Emergency Hotline number 0800 80 70 60.

Back to top